基于Maven搭建指定模块结构的多分层Java项目技术问询

Hey there! Let's walk through setting up your multi-layered Java project with Maven exactly as you described. Since you've already started with a project named flash, here's how to structure each module properly:

The root pom acts as the parent/aggregator for all modules. It should have a pom packaging type and list all child modules.

<!-- flash/pom.xml -->
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.example.flash</groupId>
    <artifactId>flash-root</artifactId>
    <version>1.0.0-SNAPSHOT</version>
    <packaging>pom</packaging>
    <name>Flash Root Project</name>

    <!-- List all child modules -->
    <modules>
        <module>flash-ear</module>
        <module>flash-common</module>
        <module>flash-dal</module>
        <module>flash-service</module>
        <module>flash-gui</module>
        <module>flash-gateway</module>
    </modules>

    <!-- Optional: Define common dependencies/plugins for all modules -->
    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>com.example.flash</groupId>
                <artifactId>flash-common</artifactId>
                <version>${project.version}</version>
            </dependency>
            <dependency>
                <groupId>com.example.flash</groupId>
                <artifactId>flash-dal</artifactId>
                <version>${project.version}</version>
            </dependency>
            <dependency>
                <groupId>com.example.flash</groupId>
                <artifactId>flash-service</artifactId>
                <version>${project.version}</version>
            </dependency>
        </dependencies>
    </dependencyManagement>
</project>

This module is shared across all layers, so it should contain reusable utilities, constants, or DTOs. Packaging type is jar.

<!-- flash/flash-common/pom.xml -->
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <parent>
        <groupId>com.example.flash</groupId>
        <artifactId>flash-root</artifactId>
        <version>1.0.0-SNAPSHOT</version>
    </parent>

    <artifactId>flash-common</artifactId>
    <packaging>jar</packaging>
    <name>Flash Common Layer</name>

    <!-- Add shared dependencies here (e.g., Lombok, Apache Commons) -->
    <dependencies>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.30</version>
            <scope>provided</scope>
        </dependency>
    </dependencies>
</project>

Handles database interactions, depends only on the CommonLayer. Packaging type is jar.

<!-- flash/flash-dal/pom.xml -->
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <parent>
        <groupId>com.example.flash</groupId>
        <artifactId>flash-root</artifactId>
        <version>1.0.0-SNAPSHOT</version>
    </parent>

    <artifactId>flash-dal</artifactId>
    <packaging>jar</packaging>
    <name>Flash Data Access Layer</name>

    <dependencies>
        <!-- Depend on CommonLayer -->
        <dependency>
            <groupId>com.example.flash</groupId>
            <artifactId>flash-common</artifactId>
        </dependency>
        <!-- Add DB dependencies (e.g., Hibernate, Spring Data JPA) -->
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-core</artifactId>
            <version>6.4.4.Final</version>
        </dependency>
    </dependencies>
</project>

Contains business logic, depends on DataAccessLayer and CommonLayer. Packaging type is jar.

<!-- flash/flash-service/pom.xml -->
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <parent>
        <groupId>com.example.flash</groupId>
        <artifactId>flash-root</artifactId>
        <version>1.0.0-SNAPSHOT</version>
    </parent>

    <artifactId>flash-service</artifactId>
    <packaging>jar</packaging>
    <name>Flash Service Layer</name>

    <dependencies>
        <dependency>
            <groupId>com.example.flash</groupId>
            <artifactId>flash-common</artifactId>
        </dependency>
        <dependency>
            <groupId>com.example.flash</groupId>
            <artifactId>flash-dal</artifactId>
        </dependency>
        <!-- Add business logic dependencies (e.g., Spring Context) -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>6.1.5</version>
        </dependency>
    </dependencies>
</project>

Web module for UI, depends on ServiceModule and CommonLayer. Packaging type is war.

<!-- flash/flash-gui/pom.xml -->
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <parent>
        <groupId>com.example.flash</groupId>
        <artifactId>flash-root</artifactId>
        <version>1.0.0-SNAPSHOT</version>
    </parent>

    <artifactId>flash-gui</artifactId>
    <packaging>war</packaging>
    <name>Flash GUI Module</name>

    <dependencies>
        <dependency>
            <groupId>com.example.flash</groupId>
            <artifactId>flash-common</artifactId>
        </dependency>
        <dependency>
            <groupId>com.example.flash</groupId>
            <artifactId>flash-service</artifactId>
        </dependency>
        <!-- Add JSF/JSP dependencies (e.g., Mojarra) -->
        <dependency>
            <groupId>org.glassfish</groupId>
            <artifactId>jakarta.faces</artifactId>
            <version>4.0.1</version>
            <scope>provided</scope>
        </dependency>
    </dependencies>

    <!-- Maven WAR plugin configuration -->
    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-war-plugin</artifactId>
                <version>3.3.2</version>
                <configuration>
                    <failOnMissingWebXml>false</failOnMissingWebXml>
                </configuration>
            </plugin>
        </plugins>
    </build>
</project>

Web module for REST APIs, depends on ServiceModule and CommonLayer. Packaging type is war.

<!-- flash/flash-gateway/pom.xml -->
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <parent>
        <groupId>com.example.flash</groupId>
        <artifactId>flash-root</artifactId>
        <version>1.0.0-SNAPSHOT</version>
    </parent>

    <artifactId>flash-gateway</artifactId>
    <packaging>war</packaging>
    <name>Flash Gateway Module</name>

    <dependencies>
        <dependency>
            <groupId>com.example.flash</groupId>
            <artifactId>flash-common</artifactId>
        </dependency>
        <dependency>
            <groupId>com.example.flash</groupId>
            <artifactId>flash-service</artifactId>
        </dependency>
        <!-- Add REST dependencies (e.g., Spring Web) -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-web</artifactId>
            <version>6.1.5</version>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-war-plugin</artifactId>
                <version>3.3.2</version>
                <configuration>
                    <failOnMissingWebXml>false</failOnMissingWebXml>
                </configuration>
            </plugin>
        </plugins>
    </build>
</project>

Packages both GUIModule and GatewayModule into an EAR for application server deployment. Packaging type is ear.

<!-- flash/flash-ear/pom.xml -->
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <parent>
        <groupId>com.example.flash</groupId>
        <artifactId>flash-root</artifactId>
        <version>1.0.0-SNAPSHOT</version>
    </parent>

    <artifactId>flash-ear</artifactId>
    <packaging>ear</packaging>
    <name>Flash EAR Module</name>

    <dependencies>
        <!-- Include web modules as EAR modules -->
        <dependency>
            <groupId>com.example.flash</groupId>
            <artifactId>flash-gui</artifactId>
            <type>war</type>
        </dependency>
        <dependency>
            <groupId>com.example.flash</groupId>
            <artifactId>flash-gateway</artifactId>
            <type>war</type>
        </dependency>
    </dependencies>

    <!-- Maven EAR plugin configuration -->
    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-ear-plugin</artifactId>
                <version>3.3.0</version>
                <configuration>
                    <version>8</version>
                    <defaultLibBundleDir>lib</defaultLibBundleDir>
                    <modules>
                        <webModule>
                            <groupId>com.example.flash</groupId>
                            <artifactId>flash-gui</artifactId>
                            <contextRoot>/flash-gui</contextRoot>
                        </webModule>
                        <webModule>
                            <groupId>com.example.flash</groupId>
                            <artifactId>flash-gateway</artifactId>
                            <contextRoot>/flash-gateway</contextRoot>
                        </webModule>
                    </modules>
                </configuration>
            </plugin>
        </plugins>
    </build>
</project>

Final Project Directory Structure #

Once all modules are created, your project will look like this:

flash/
├── pom.xml                # Root POM
├── flash-ear/
│   └── pom.xml            # EAR module
├── flash-common/
│   └── pom.xml            # Common layer
├── flash-dal/
│   └── pom.xml            # Data access layer
├── flash-service/
│   └── pom.xml            # Business service layer
├── flash-gui/
│   ├── pom.xml            # JSF/JSP web module
│   └── src/main/webapp/   # UI resources
└── flash-gateway/
    ├── pom.xml            # REST web service module
    └── src/main/webapp/

Building the Project #

From the root flash/ directory, run:

mvn clean install

This will build all modules and generate the final EAR file in flash-ear/target/flash-ear-1.0.0-SNAPSHOT.ear, ready for deployment to servers like WildFly or WebLogic.

内容的提问来源于stack exchange，提问作者Hosein Aqajani